Elo-like systems (or various other rating systems) are often as part of a matchmaking algorithm - since you can easily calculate expected game win percentages f

Elo-like systems (or various other rating systems) are often as part of a matchmaking algorithm - since you can easily calculate expected game win percentages for each party, and this allows you to create more enjoyable matchups. An example of this happens even in online chess: you're much more likely to be paired against a player with a similar rating, because you're much more likely to enjoy a match against someone similarly skilled.